Evaluation of Gadolinium Based Contrast Agents for Portable MR Imaging Systems

Inclusion Criteria To be eligible to participate in this study, an individual must meet all the following criteria: * Age ≥18 years Clinical indication of suspected or known brain lesion(s) with focal blood-brain barrier disruption. Preferably, at least one previously documented brain lesion with focal areas of blood-brain barrier disruption categorizable as: * intra-axial tumor(s) * extra-axial tumor(s) * infection/inflammatory lesion(s) * Cleared for portable MRI (pMRI) and intravenous GBCA administration per site policy. * Adequate peripheral venous access for contrast injection. * Able to provide informed consent and comply with brief supine imaging (pre- and post-contrast) Exclusion Criteria Participants will be excluded if they meet any of the following criteria: * Metallic clips or devices in the brain or eye. * Body weight greater than 200 kg. * Inability to fit or be positioned appropriately within the Swoop® Portable MR Imaging® System. * Inability to remain still or lie flat during the imaging period. * Not cleared for GBCA administration due to known hypersensitivity, allergy, or contraindication. * Severe renal impairment (eGFR \< 30 mL/min/1.73 m²) or acute kidney injury. * History of severe reaction to any gadolinium-based contrast agent. * GBCA administration within the prior 48 hours (or alternative clearance window defined by institution) * Known or suspected pregnancy at the time of imaging. * Any medical or behavioral condition that, in the inv…